Soil Invertebrates in Different Land Use Systems： How Integrated Production Systems and Seasonality Affect Soil Mesofauna Communities

The soil mesofauna plays a role in organic matter comminution and decomposition, and can be used as bioindicators, since they are sensitive to soil management, vegetation and climate changes. Hence, this study aimed to evaluate mesofauna density and diversity in different land use systems to identify faunal relationships with soil properties, management and seasonality. The study area included five land use systems in Ponta Grossa municipality, Parana State： integrated crop-livestock （ICL）, integrated crop-livestock-forestry （ICLF）, grazed native pasture （NP）, Eucalyptus dunnii plantation （EU） and no-tillage （NT） cropping systems. In each system, eight soil samples for mesofauna were collected with Berlese funnels of 8 cm diameter along a transect in three replicate plots of 50 m × 100 m. For physical and chemical analysis, soil was sampled at five points per plot in two seasons： winter 2012 and autumn 2013. Data were statistically analyzed using ANOVA and Duncan＇s test （P 〈 0.05）, nonparametric statistics （when necessary） and redundancy analysis （RDA）. Diversity was calculated based on the group richness and Simpson index. The main mesofauna groups found were： Acarina, Collembola and Hymenoptera. Diplopoda, Enchytraeidae, Isopoda, Collembola, Hemiptera, Hymenoptera and Coleoptera larvae were more abundant in autumn than winter. Soil moisture was the main factor responsible for higher mesofauna abundance in autumn. Integrated production systems, especially ICLF had similar invertebrate community abundance and composition with EU, while NT favored Oribatid mites, although the use of insecticides, herbicides and fungicides reduced total mesofauna density. Most correlations between mesofauna and physical-chemical attributes in the winter were not observed in the autumn and vice versa, revealing that there are more factors involved in regulating soil mesofauna distribution.

Using dung beetles to evaluate the effects of urbanization on Atlantic Forest biodiversity

We used dung beetles to evaluate the impact of urbanization on insect biodi- versity in three Atlantic Forest fragments in Londrina, Parana, Brazil. This study provides the first empirical evidence of the impact of urbanization on richness, abundance, compo- sition and guild structure of dung beetle communities from the Brazilian Atlantic Forest. We evaluated the community aspects （abundance, richness, composition and food guilds） of dung beetles in fragments with different degrees of immersion in the urban matrix using pitfall traps with four alternative baits （rotten meat, rotten fish, pig dung and decaying ba- nana）. A total of 1 719 individuals were collected, belonging to 29 species from 11 genera and six Scarabaeinae tribes. The most urban-immersed fragment showed a higher species dominance and the beetle community captured on dung presented the greatest evenness. The beetle communities were distinct with respect to the fragments and feeding habits. Except for the dung beetle assemblage in the most urbanized forest fragment, all others exhibited contrasting differences in species composition attracted to each bait type. Our results clearly show that the degree of urbanization affects Atlantic Forest dung beetle communities and that the preservation of forest fragments inside the cities, even small ones, can provide refuges for Scarabaeinae.